This application relates to a geared gas turbine engine wherein a fan rotor is driven through a non-epicyclic gear reduction.
Gas turbine engines are known and typically include a fan delivering air into a bypass duct as propulsion air and further into an engine core including a compressor. The air is compressed and delivered into a combustor where it is mixed with fuel and ignited. Products of this combustion pass downstream over turbine rotors, driving them to rotate.
Historically, a fan drive turbine has driven the fan as a spool and at a single speed. More recently, a gear reduction has been placed between the fan and the fan drive turbine. This allows the fan to rotate at slower speeds, which has beneficial characteristics.
To date, the gear reduction utilized in geared gas turbine engines has been an epicyclic gear system.